Infineon GTM ATOM PWM 1 User manual

Brand: Infineon

Model: GTM ATOM PWM 1

Type: User manual

AURIX™ TC2xx Microcontroller Training

V1.0.0

GTM_ATOM_PWM_1

GTM ATOM PWM generation

Please read the Important Notice and Warnings at the end of this document

Scope of work

GTM ATOM is used to generate a PWM signal, which is driving the

intensity of an LED.

The LED is driven by pin 0 of the port 13. The state of the pin is controlled by

the PWM signal generated by the ATOM timer of GTM.

Introduction

› The Generic Timer Module (GTM) is a modular timer unit designed to

accommodate many timer applications.

› It has an in-built Advanced Router Unit (ARU) that can be used to

exchange specific data between sub-modules without CPU interaction.

› The ARU-connected Timer Output Module (ATOM), which is part of the

GTM, is able to generate complex output signals.

› The Clock Management Unit (CMU) is responsible for clock generation of

the GTM. The Configurable Clock Generation Subunit (CFGU) provides

eight clock sources for the GTM submodules: TIM, TBU, MON and ATOM.

Hardware setup

This code example has been

developed for the board

KIT_AURIX_TC297_TFT_BC-Step.

LED D107 (1) is used for this

example.

Implementation

Configuring the ATOM

The configuration of the ATOM is done once in the setup phase by calling the initialization

function initGtmAtomPwm() containing the following steps:

› Enable the GTM by calling the function IfxGtm_enable().

› Set the CMU clock 0 frequency to 1 MHz with the function

IfxGtm_Cmu_SetClkFrequency().

› Enable the CMU clock 0 by calling the function IfxGtm_Cmu_enableClocks().

The function IfxGtm_Atom_Pwm_initConfig() initializes an instance of the structure

IfxGtm_Atom_Pwm_Config with its default values.

Implementation

Configuring the ATOM

› The IfxGtm_Atom_Pwm_Config structure allows to set the following parameters to initialize

the module:

– atom – Selection of the ATOM which is counting (ATOM 2 in this example)

– atomChannel – Selection of the channel which is driving the LED (Channel 5 in this

example)

– period – Setting of the period for the PWM signal to the desired value

– pin.outputPin – Selection the LED as output pin

– synchronousUpdateEnable – Enabling of Synchronous Update of the timer

› After configuration, the function IfxGtm_Atom_Pwm_init() initializes and activates the

ATOM with the user configuration.

› Start the PWM with the function IfxGtm_Atom_Pwm_start().

All the functions used for the configuration of the ATOM are provided by the iLLD header

IfxGtm_Atom_Pwm.h.

Implementation

Setting the duty cycle

The setting of the duty cycle is done by calling the function setDutyCycle(), which contains the

following steps:

› Set the dutyCycle parameters of the instance of the configuration structure to set theduty

cycle for the PWM signal to the desired value

› Call the function IfxGtm_Atom_Pwm_init() to re-initialize and re-activates the ATOM with

the new configuration.

The functions IfxGtm_Atom_Pwm_init() is provided by the iLLD header

IfxGtm_Atom_Pwm.h.

Fading the LED

The fading of the LED is done in the function fadeLED() by repetitively adding or removing a

step value to the duty cycle of the PWM.

Implementation

Calculation example

The CMU clock 0 frequency (f

clk0

) is set to 1 MHz in this example. The period value to have the

desired PWM frequency (f

PWM

) is calculated with the following formula:

 









In this example:  

 

 

  

PWM signal

Period of PWM

CMU clock 0

Frequency of the

clock

Duty cycle of the PWM

Run and Test

After code compilation and flashing the device, observe the LED D107 (1),

which should be fading.

References

› More code examples can be found on the GIT repository:

› https://github.com/Infineon/AURIX_code_examples

› For additional trainings, visit our webpage:

› https://www.infineon.com/aurix-expert-training

› AURIX™ Development Studio is available online:

› https://www.infineon.com/aurixdevelopmentstudio

› Use the „Import...“ function to get access to more code examples.

› For questions and support, use the AURIX™ Forum:

› https://www.infineonforums.com/forums/13-Aurix-Forum

IMPORTANT NOTICE

The information given in this document shall in no

event be regarded as a guarantee of conditions or

characteristics (“Beschaffenheitsgarantie”) .

With respect to any examples, hints or any typical

values stated herein and/or any information

regarding the application of the product, Infineon

Technologies hereby disclaims any and all

warranties and liabilities of any kind, including

without limitation warranties of non-infringement

of intellectual property rights of any third party.

In addition, any information given in this

document is subject to customer’s compliance

with its obligations stated in this document and

any applicable legal requirements, norms and

standards concerning customer’s products and

any use of the product of Infineon Technologies in

customer’s applications.

The data contained in this document is exclusively

intended for technically trained staff. It is the

responsibility of customer’s technical

departments to evaluate the suitability of the

product for the intended application and the

completeness of the product information given in

this document with respect to such application.

For further information on the product,

technology, delivery terms and conditions and

prices please contact your nearest Infineon

Technologies office (www.infineon.com).

WARNINGS

Due to technical requirements products may

contain dangerous substances. For information

on the types in question please contact your

nearest Infineon Technologies office.

Except as otherwise explicitly approved by

Infineon Technologies in a written document

signed by authorized representatives of Infineon

Technologies, Infineon Technologies’ products

may not be used in any applications where a

failure of the product or any consequences of the

use thereof can reasonably be expected to result

in personal injury.

Edition 2019-10

Published by

Infineon Technologies AG

81726 Munich, Germany

Do you have a question about this

document?

Email: erratum@infineon.com

Document reference

GTM_ATOM_PWM_1

Trademarks

All referenced product or service names and trademarks are the property of their respective owners.

Infineon GTM ATOM PWM 1 User manual

Infineon GTM ATOM PWM 1 User manual

Infineon GTM ATOM PWM 1 User manual

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